伴随动力机械轻量化的发展，运动部件与机体的质量比增大，将引发明显的机体振动。为研究轻量化条件下的动力机械机体固有频率与内部质量比的关系，本文设计了模拟动力机械不同质量比的实验台架，在其静态和动态工况下进行振动测试，发现两者固有频率存在差异；建立起内力联接的动力隔振内力拓扑模型，解释固有频率差异的原因；推导关于质量比、频率比的二元动力传递函数并从侧视和俯视两个角度对三维曲面进行分析。结果表明，在轻量化背景下，动力机械机体固有频率存在随着质量比增加而向大值漂移的现象，本文二元动力传递函数能够表达内力模型下动力机械固有频率的分布特性，可以为动力机械系统参数辨识及隔振器设计提供理论基础。

With the constant development of lightweight power machinery, the mass ratio of the moving parts to the body increased, and consequently induce more obvious body vibration. In order to study the relationship between the natural frequency of the power machinery body and the internal mass ratio under the condition of lightweight, experimental bench for simulating different mass ratios of power machinery was designed. Vibration tests were carried out under static and dynamic conditions, suggesting the existence of differences in the natural frequencies. The moving parts and the body were connected by the internal force, and the internal force topology model of dynamic vibration isolation was established to interpret the difference in the natural frequency. The two-parameter dynamic transfer function of the mass and frequency ratios is derived, and the three-dimensional surface of dynamic transfer function is analyzed from two angles of side view and top view. The results show that under the background of lightweight, The natural frequency of power machinery body drifts to the maximum value with the increase of mass ratio. The binary dynamic transfer function established in this paper can express the distribution characteristics of the natural frequency of the power machinery under the internal force model, and has better applicability, and provides a theoretical basis for parameter identification and vibration isolators design of power mechanical systems.